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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent LEFT JOIN category ON category.patent = patent.patent AND category.type = patent.type WHERE (category.class = '425') AND (category.subclass = '397') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '425'; Subclass is '397';

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T / S Patent Date Description Patentee Category Assigned To
 1904
U 759,429 May 10, 1904 Machine for Heading Insulators
Machine for forming the heads on pottery or porcelain wall tubes		 FIRESTONE, Truman L.
 Wall Tube  

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